Shapes and Designs - Edges and Corners

Edges are the boundary lines of a shape. They can be straight, like the side of a notebook, or curved, like the edge of a circular plate. In 3D shapes, an edge is where two flat surfaces meet.

Corners, also known as vertices, are the sharp points where two or more edges meet. For example, a square has $4$ corners where its straight sides join together. Shapes like circles and spheres have no corners.

2D Shapes and their properties: A triangle has $3$ straight edges and $3$ corners. A square and a rectangle both have $4$ straight edges and $4$ corners. A circle is unique because it has $1$ continuous curved edge and $0$ corners, appearing perfectly round like a $1$-rupee coin.

3D Shapes and their properties: A cube or cuboid (like a wooden block) has $12$ straight edges and $8$ corners. A cylinder (like a soda can) has $2$ curved edges and $0$ corners. A sphere (like a ball) has no edges and no corners at all.

A cone is a special 3D shape that looks like a party hat. It has $1$ curved edge at the bottom where the circular base meets the side, and it has $1$ corner (vertex) at the very top point.

Tangrams are ancient Chinese puzzles made of $5$ or $7$ geometric pieces called 'tans'. These pieces, which include triangles of different sizes, a square, and a parallelogram, can be arranged to create various pictures of animals, people, or objects.

Tiling or Tessellation is the process of covering a flat surface using repeating shapes so that there are no gaps and no overlaps. Imagine a floor covered in square tiles; the corners and edges fit perfectly to create a continuous pattern.